Technical Field
The present disclosure relates to an electronic device having a touch sensor and a driving method thereof.
Discussion of the Related Art
As the weights and thicknesses of electronic devices such as home appliances and portable information devices are decreased, a user input means is changed from a button type switch to a touch sensor. Accordingly, electronic devices such as a recent display device have a touch sensor (or touchscreen).
The touch sensor is essentially included in portable information devices such as smartphones and is also applied to notebook computers, computer monitors, home appliances and the like. Recently, a technology for embedding the touch sensor in a pixel array of a display panel (referred to as “in-cell touch sensor” hereinafter) has been proposed.
The in-cell touch sensor technology can install touch sensors in a display panel without increasing the thickness of the display panel. An electronic device having an in-cell touch sensor time-divides a pixel driving period (which is also referred to as “display driving period”) and a touch sensor driving period (which is also referred to as “touchscreen driving period”) in order to reduce the mutual influence of pixels and touch sensors due to coupling of the pixels and the touch sensors.
The in-cell touch sensor technology uses electrodes connected to the pixels of the display panel as electrodes of the touch sensors. For example, the in-cell touch sensor technology divides a common electrode for supplying a common voltage to pixels of a liquid crystal display and uses the divided common electrodes as electrodes of touch sensors.
In addition, in the in-cell touch sensor technology, a function of entering a sleep mode (or idle mode) when a display device is not used has been proposed. The sleep mode reduces power consumption of the display device by allowing the display panel to be idle when the display device is not used. However, it is necessary to continue research on a sleep mode for reducing power consumption.